Yesterday, some wonderful friends here in #Argentina told us the secrets of drinking mate (yerba mate) properly:
1) Drink all the mate in the offered matero, then return it to the person with the thermos.
2) Don't move the metal straw around. No stirring!
3) Don't say "Gracias" until you don't want any more.

They all laughed when I said the essence of ethnographic research was making these kinds of mistakes until someone corrected you. I'll drink mate correctly from now on! #Ushuaia